diff --git a/WS1920/hw5-setup.txt b/WS1920/hw5-setup.txt new file mode 100644 index 0000000000000000000000000000000000000000..b888e87321e15a6ed42d1a643cffe8be2394fd6a --- /dev/null +++ b/WS1920/hw5-setup.txt @@ -0,0 +1,103 @@ +% Map Coloring + +% Original problem: https://www.tjhsst.edu/~rlatimer/assignments2004/colors.txt + +% It's known that only 4 colors are needed to paint any map so that no two neighboring states have the same color. +% Write a Prolog program that receives a map and a list of 4 colors and produces a colored map. +% The map is represented by a list of states, each of which is a state name and a list of neighboring states. +% For example, the maps of Australia and Western Europe are represented by the following maps. + + +% Maps of Australia and West Europe, colors, define getcolor + +map('Australia', + [wa: [nt,sa], nt: [wa,sa,qld], qld:[nt,sa,nsw], + nsw: [qld,sa,vic], vic: [sa,nsw], tas:[], + sa: [wa,nt,qld,nsw,vic]]). + +map('West Europe', + [portugal: [spain], + spain: [portugal, france], + belgium: [france, holland, luxembrg, germany], + holland: [belgium, germany], + luxembrg: [france, belgium, germany], + switzerld: [france,germany,austria, italy], + italy: [france,switzerld, austria], + austria: [germany, switzerld, italy], + france: [spain,belgium,luxembrg, germany,switzerld, italy], + germany:[holland,belgium,luxembrg,france,switzerld, austria]]). + +colors([red,green,blue,yellow]). + + +% - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - +% Edit section + +arrangecolors([],_,ColoredMap,ColoredMap). +% Tracing: +% :- write('Colormap='), write(ColoredMap),nl. +arrangecolors([Country:Neighbors|Rest], ColorList, TempList, ColoredMap) :- + member(Color,ColorList), +% Tracing: +% write('Color:'), write(Color),write(' TempList:'), write(TempList),nl, + different(Color,Neighbors,TempList) + arrangecolors(Rest,ColorList,[Country:Color|TempList], ColoredMap). + +% TempList is in the format [country1:color1,country2:color2,...] +restrictedness(Neighbors,TempList,R) :- + length(Neighbors,1), + length(TempList,1), + R = 1. + + +% - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - +% Maybe useful things + +findneighbors(X, Map, Who) :- + map(Map, Countries), + neighbors(X,Countries,Who). + +neighbors(_,[],[]). +neighbors(X,[X:Neighbors|_], Neighbors) :- !. % Try this without the ! +neighbors(X,[_|RestofCountries], Neighbors) :- + neighbors(X,RestofCountries, Neighbors). + +adjacent(X,Y,Map) :- + findneighbors(X, Map, Countries), + member(Y, Countries). + + +% - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - +% This you will most likely use + +different(C, Nbs, [S1:C1|Rest]) :- + not((member(S1,Nbs), C = C1)), + different(C, Nbs,Rest). +different(_,_,[]). + +availablecolors(_,[],Colors,Colors). +availablecolors(Neighbors,[NB:Color|TempListTail],TempColors,Colors) :- + member(NB,Neighbors) -> + availablecolors(Neighbors,TempListTail,[Color|TempColors],Colors); + availablecolors(Neighbors,TempListTail,TempColors,Colors). + +countrieswithconstraints([],_,L,L). +countrieswithconstraints([Country:Neighbors|Rest],TempList,Accumulator,CountriesWithConstraints) :- + countrieswithconstraints(Rest,TempList,[R-(Country:Neighbors)|Accumulator],CountriesWithConstraints), + restrictedness(Neighbors,TempList,R). + +sortedcountries(Countries,TempList,SortedCountries) :- + countrieswithconstraints(Countries,TempList,[],CountriesWithConstraints), + keysort(CountriesWithConstraints,SortedCountries). + + +% - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - +% Main +paint(Map,ColoredMap) :- + map(Map, Countries), + colors(ColorList), +% Tracing: +% write('ColoredMap is '), write(ColoredMap), nl. + arrangecolors(Countries,ColorList,[], ColoredMap). + +% paint('Australia',ColoredMap). \ No newline at end of file